| HS Code | 897991 |
| Density | 1.23 g/cc |
| Water Absorption | 0.30% |
| Moisture Absorption At Equilibrium | 0.70% |
| Linear Mold Shrinkage | 0.0020 cm/cm |
| Tensile Strength Ultimate | 175 MPa |
| Tensile Modulus | 17.0 GPa |
| Flexural Modulus | 14.0 GPa |
| Flexural Yield Strength | 230 MPa |
| Elongation At Break | 1.5% |
| Izod Impact Notched | 4.00 kJ/m² |
| Izod Impact Unnotched | 35.0 kJ/m² |
| Coefficient Of Linear Thermal Expansion | 20.0 µm/m-°C |
| Thermal Conductivity | 0.350 W/m-K |
| Melting Point | 178 °C |
| Heat Deflection Temperature 0 45 Mpa | 175 °C |
| Heat Deflection Temperature 1 8 Mpa | 170 °C |
As an accredited Overview of materials for Nylon 12, Carbon Fiber Filled factory, we enforce strict quality protocols—every batch undergoes rigorous testing to ensure consistent efficacy and safety standards.
| Packing | Packaging: One sealed folder containing a technical overview of Nylon 12, Carbon Fiber Filled materials, with property data and processing guidelines. Quantity: 1 folder. |
| Container Loading (20′ FCL) | Bagged Nylon 12 carbon fiber filled material palletized and secured in a 20-foot full container load, optimized for safe transport. |
| Shipping | Shipping description: Nylon 12 carbon fiber filled composite, in pellet form. Not regulated as dangerous goods for transport. No UN number required. Avoid dust generation; keep away from ignition sources. Pack in sealed, grounded containers to prevent static discharge. Not marine pollutant. |
| Storage | Store in a sealed, original container in a cool, dry, well-ventilated area away from direct sunlight and heat sources. Protect from moisture to prevent water absorption, which can degrade properties. Keep away from ignition sources and incompatible materials. Avoid generating carbon fiber dust; use proper handling procedures. |
| Shelf Life | Store sealed in original container, away from moisture and heat. Shelf life is indefinite when properly stored. |
In underhood environments where peak soak temperatures can exceed 120°C and intermittent exposure to engine oil, hot coolant, and de-icing salts is expected, the compound is supplied as a ready-to-mold granulate with a carbon fiber loading of 15–25 wt% already dispersed in the polyamide 12 matrix. The carbon fiber loading in each downstream sector is a compound composition specification, not a downstream additive ratio; converters do not add fiber during injection molding or powder bed fusion.
Material compliance for underhood brackets and sensor mounts references ISO 527-2:2012 for tensile properties, ISO 179-1/1eU:2010 for unnotched Charpy impact, ISO 75-2:2013 for heat deflection temperature at 1.8 MPa, and ISO 175:2010 for chemical resistance after immersion in ASTM reference fuel C and 5W-30 engine oil. OEM part approvals usually require additional validation under ISO 16750-3:2012 or an equivalent vehicle-environment cycling specification; generic compound data do not replace part-level thermal shock and fluid-exposure testing. The carbon fiber loading is set at 15–25 wt% in this sector because load-bearing stiffness increases with fiber content, while Charpy impact drops rapidly above 25 wt%. Granulate is dried to ≤0.1% water by weight, per ISO 15512:2019, in a desiccant dryer at 80°C for 4–8 h with a dew point of −40°C or lower. If ambient relative humidity exceeds 60%, the dried granulate is conveyed directly from the dryer to the injection molding machine hopper under closed dry-air conveying; open storage beyond 30 min can reintroduce surface moisture and produce splay. Injection molding is performed on a single-screw reciprocating machine with an L/D ratio of 20:1–25:1 and a compression ratio of 2.0:1–2.5:1. Barrel temperatures from 230°C to 260°C and mold temperatures of 40–80°C are typical, while back pressure is held below 0.5 MPa to limit fiber-length reduction along the screw. Gate diameter is maintained above 1.5 mm, injection speed is set at 30–80 mm/s, and the melt cushion is held at 3–6 mm because narrow gates or excessive shear cause fiber blackening and localized loss of stiffness at weld lines. Terminal parts produced under this profile include throttle body brackets, air intake sensor mounts, cable guides, clip retainers, and charge air duct flanges where dimensional stability and hydrocarbon resistance supersede maximum impact toughness. Direct contact with aluminum substrates under saline spray requires a barrier coating or isolation boss because carbon fiber can promote galvanic corrosion of the metal.
Because mechanical response is loading-dependent, the following ranges from commercial datasheets are used for preliminary design checks; they are not a single-lot certificate of analysis.
| Carbon fiber loading | Tensile modulus (ISO 527-2:2012) | Tensile strength (ISO 527-2:2012) | Flexural modulus (ISO 178:2019) | Charpy unnotched (ISO 179-1/1eU:2010) | HDT at 1.8 MPa (ISO 75-2:2013) | Density (ISO 1183-1:2019) | Surface resistivity (IEC 60093) |
|---|---|---|---|---|---|---|---|
| 10 wt% | 2,000–3,200 MPa | 55–70 MPa | 1,800–2,900 MPa | 35–55 kJ/m² | 60–80°C | 1.07–1.12 g/cm³ | 107–1010 Ω/sq |
| 20 wt% | 3,500–5,500 MPa | 65–85 MPa | 3,200–5,000 MPa | 20–40 kJ/m² | 80–110°C | 1.14–1.20 g/cm³ | 104–108 Ω/sq |
| 30 wt% | 6,000–8,500 MPa | 80–110 MPa | 5,500–7,500 MPa | 15–25 kJ/m² | 100–130°C | 1.21–1.28 g/cm³ | 102–105 Ω/sq |
Pneumatic valve bodies and actuator end caps are produced from the same compound family but at a higher carbon fiber loading of 20–30 wt% to suppress creep under continuous internal pressure cycling. The dimensional stability requirement is governed by ISO 294-4:2018 for shrinkage measurement, ISO 178:2019 for flexural modulus, and ISO 1133-1:2022 for melt flow rate as an incoming-lot control. Because carbon fiber lowers melt flow considerably, a medium-viscosity PA12 base resin is selected; MFR at 235°C/5 kg typically remains in the 2–10 g/10 min range across commercial grades, and lower values indicate fiber-induced wall slip variability during mold filling. The process uses a valve-gated cold-runner mold to reduce fiber breakage at the gate; hot-runner systems with small needle tips below 1.2 mm are avoided because local shear heating above 290°C can yellow the matrix. Mold temperatures are set at 60–100°C to allow sufficient surface replication while minimizing post-mold warpage; ejection is delayed until the part surface temperature falls below 80°C because early ejection causes pin push-out distortion at boss locations. Terminal product types include pneumatic valve bodies, actuator end caps, spool sleeves, manifold plates, air cylinder end plates, and regulator housings. The operational boundary is that carbon fiber is abrasive; screw and barrel wear accelerates when mineral-filled grades are alternated without purging. Bimetallic barrels and hardened screws with a surface hardness of ≥60 HRC are specified for production runs exceeding 50,000 cycles; published data for longer-run wear life in specific valve body tools is limited and must be monitored by dimensional drift checks on sealing faces.
In offshore dynamic umbilical service, carbon fiber filled nylon 12 is specified for components that require low water absorption and resistance to aliphatic hydrocarbons. The carbon fiber loading is held at 25–30 wt% for wear pads and centralizer fins, where surface velocity and contact pressure produce frictional heating. Compliance for hydrocarbon exposure references ISO 23936-1:2009 for thermoplastic components in oil and gas production and NORSOK M-710 for sour service aging, with water absorption controlled under ISO 62:2008. The production route is either injection molding of near-net shapes or compression molding of thick sheet stock that is then CNC machined into wear pads, centralizer fins, ROV manipulator components, and cable protection guides. Machining is carried out with polycrystalline diamond end mills at low feed force because carbon fiber causes severe tool wear; cutting speed is typically reduced by 30–50% compared with unfilled PA12 stock. In sour gas environments, the operational boundary is not generic PA12 but the compound's stabilization package; long-term exposure to pressurized H₂S at temperatures above 80°C is not supported by published data for this specific configuration unless a dedicated heat/sour stabilizer package is specified. Direct contact with aluminum structural frames in seawater spray is isolated with elastomer or polymer shims to avoid galvanic coupling through the carbon fiber phase.
Transtibial prosthetic sockets requiring both load-bearing stiffness and skin-contact compatibility are fabricated from carbon fiber filled nylon 12 sheet specified at 12–20 wt% carbon fiber to reduce creep without eliminating edge-trimming ductility needed for definitive socket fabrication. The compliance pathway includes ISO 10993-5:2009 for in vitro cytotoxicity, ISO 10993-10:2010 for skin sensitization, and ISO 22523:2006 for external limb prostheses where applicable. Sheet or granulate is dried to ≤0.1% moisture and thermally formed on positive plaster models at sheet-surface temperatures between 190°C and 220°C; drag forming with infrared pyrometer feedback is used because convective ovens create edge overheating and surface fiber bloom. Injection-molded foot shells and ankle joint housings use barrel profiles of 230–250°C and mold temperatures of 40–70°C; the narrow reheat window of approximately ±5°C before surface oxidation requires closed-loop heater control rather than manual dwell timing. Because fiber orientation during drape forming is anisotropic, finished sockets are flexure-tested per ISO 10328 at the proximal brim and distal attachment points instead of relying solely on isotropic tensile data. Terminal product types include transtibial and transfemoral check sockets, definitive laminate-reinforced sockets, drop-in orthotic shell inserts, and dynamic response foot outer shells. Process scrap is not reground into structural sockets beyond 10% recycled content because repeated heat cycles degrade the carbon fiber-polymer interface and lower distal cup fatigue resistance.
Surface resistivity in carbon fiber filled nylon 12 shifts from the insulating range of unfilled polyamide 12 toward 104–109 Ω/sq depending on fiber loading, fiber orientation, and the presence of weld lines. For ESD protective housings and instrument enclosures, a loading of 10–15 wt% carbon fiber is used because higher loadings increase conductivity but degrade drop impact and thin-wall moldability. Compliance is verified under IEC 60093 for surface resistivity and IEC 61340-5-1:2016 for ESD protected area materials; UL 94 flame rating is not inherent to carbon fiber filled PA12 and requires a separate flame-retardant formulation if V-0 or V-2 is specified. The downstream process is injection molding with a freeze-free hot runner or direct sprue gate located away from living hinges and snap-fit details because weld lines generate localized insulating regions that fail ESD audits. Mold temperatures of 40–60°C and melt temperatures of 235–250°C are used; high melt temperature reduces surface resistivity slightly by improving fiber wetting but increases the risk of surface gloss variation. Terminal product types include ESD trays, PCB handling fixtures, connector housings, sensor enclosures, and laboratory instrument covers where residual charge must decay within 2 seconds from 1,000 V to 100 V per IEC 61340-5-1:2016 test method. The material is not specified for direct high-voltage insulation; carbon fiber phase creates discrete conductive paths through the wall thickness, and creepage distance requirements under IEC 60664-1 must be evaluated on the finished assembly, not on the compound.
The following compliance matrix consolidates the primary material standards that govern each downstream sector; it is not a substitute for finished-part certification, which must account for geometry, tooling, and regulatory jurisdiction.
| Downstream sector | Primary material standard | Performance check | Additional boundary standard |
|---|---|---|---|
| Automotive underhood | ISO 527-2:2012 | Tensile modulus ≥ 3,500 MPa after conditioning | ISO 175:2010 fluid ageing, ISO 16750-3:2012 part-level cycling |
| Industrial pneumatic | ISO 178:2019 | Flexural modulus 3,000–5,500 MPa after 24 h at 23°C | ISO 294-4:2018 shrinkage, ISO 1133-1:2022 MFR |
| Oil and gas wear | ISO 23936-1:2009 | Hardness and dimensional retention after hydrocarbon ageing | NORSOK M-710 sour service aging, ISO 62:2008 water absorption |
| Medical orthotics/prosthetics | ISO 10993-5:2009 | Cytotoxicity | ISO 10993-10:2010 sensitization, ISO 10328 structural test |
| ESD electronics | IEC 60093 | Surface resistivity 104–109 Ω/sq | IEC 61340-5-1:2016, IEC 60664-1 creepage |
| Additive manufacturing | ASTM F3091/F3091M-14 | XY/Z tensile strength ratio documented | ISO/ASTM 52900:2021, ISO 1183-1:2019 density |
Because carbon fiber absorbs laser energy differently from unfilled polyamide 12 powder, powder bed fusion builds are not qualified by machine default parameters alone. Laser-based systems running 30–100 W CO₂ or fiber laser energy process PA12-CF powder at a carbon fiber loading of 15–20 wt%. The powder specification is controlled by particle size distribution, typically 20–80 μm D50, and a refresh ratio of 30–50% used powder to maintain bed density and re-coating uniformity. The production process uses a layer thickness of 0.1 mm, a laser scan speed and hatch spacing defined by the machine manufacturer, and a chamber temperature held within ±2°C of the PA12 recrystallization window to avoid curl. First-article builds must include XY and Z tensile specimens tested per ISO 527-2:2012 and density coupons per ISO 1183-1:2019; Z-axis tensile strength is commonly 30–50% lower than XY strength due to interlayer bonding. Compliance for part certification references ASTM F3091/F3091M-14 for powder bed fusion of plastic parts and ISO/ASTM 52900:2021 for terminology, while dimensional inspection fixtures follow ISO 2768-1 general tolerances unless customer-specific geometrical product specifications apply. Terminal product types include assembly jigs, robotic end-of-arm tooling, drone arm brackets, production fixtures, contour gauges, and vacuum-forming tools that require higher stiffness than unfilled PA12 at elevated shop-floor temperatures. Parts with wall thickness below 1 mm exhibit powder adhesion and warpage; hole diameters below 2 mm are drilled or reamed after build because as-built holes shrink non-uniformly along the anisotropic fiber direction. Post-process bead blasting with 0.1–0.3 mm ceramic media is required to remove partially fused powder, but aggressive blasting rounds sharp edges and alters the surface resistivity of ESD-capable fixtures.
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Carbon-fibre-filled Nylon 12 is a semi-crystalline polyamide 12 matrix compound reinforced with chopped PAN-based carbon fibre at loadings typically between 10 wt% and 30 wt%. Commercial designations include Ensinger TECAFIL PA12 CF20 for machined stock shapes and analogous 20 wt% carbon fibre compounds from RTP Company and LUVOCOM; the numerical suffix generally indicates nominal carbon fibre content. Representative 20 wt% carbon fibre compounds report density of 1.05–1.08 g/cm³ when measured according to ISO 1183-1:2019, tensile modulus of 9,000–12,000 MPa according to ISO 527-2:2012, and deflection temperature under load of 160–175 °C at 1.8 MPa according to ISO 75-2:2013. The matrix contributes low equilibrium moisture absorption and resistance to oils, road salts, and aliphatic hydrocarbons, while the carbon fibre raises specific stiffness, lowers coefficient of linear thermal expansion, and introduces measurable electrical conductivity at higher loadings. Unlike neat PA12, the carbon fibre grade is selected when creep, thermal expansion, and moisture-induced dimensional change must remain within narrow tolerance bands in load-bearing housings, brackets, and rotating components.
| Property | Test method | PA12 + 20 wt% CF | PA12 + 30 wt% CF | Unfilled PA12 | PA12 + 30 wt% GF |
|---|---|---|---|---|---|
| Density | ISO 1183-1:2019 | 1.05–1.08 g/cm³ | 1.09–1.14 g/cm³ | 1.01–1.02 g/cm³ | 1.24–1.28 g/cm³ |
| Tensile modulus | ISO 527-2:2012 | 9,000–12,000 MPa | 15,000–20,000 MPa | 1,500–1,800 MPa | 6,000–8,000 MPa |
| Tensile strength | ISO 527-2:2012 | 120–150 MPa | 150–180 MPa | 45–50 MPa | 90–110 MPa |
| Elongation at break | ISO 527-2:2012 | 2.0–4.0% | 1.5–3.0% | greater than 50% | 3.0–5.0% |
| Flexural modulus | ISO 178:2019 | 10,000–12,000 MPa | 16,000–18,000 MPa | 1,300–1,500 MPa | 5,500–7,500 MPa |
| Deflection temperature under load | ISO 75-2:2013 | 160–175 °C | 165–180 °C | 50–55 °C | 150–170 °C |
The mechanical comparison in Table 1 indicates that carbon fibre improves tensile modulus by a factor of 6 to 8 over unfilled PA12 and by 1.4 to 2.0 over a 30 wt% glass fibre reference, while reducing density by roughly 15–20% relative to glass-filled PA12. The elongation at break of carbon fibre grades falls to 2.0–4.0%, which removes the ductile failure mode of unfilled PA12 and requires design review for snap fits, press-fits, and weld lines. The numerical values are grade-specific; mould flow path, fibre orientation, and regrind content alter final part data. Where published datasheets do not cover a specific wall thickness or flow length, tensile values should be verified using ISO 527-2/1A specimens rather than extrapolated from raw material data.
The principal differences are specific stiffness, density, wear behaviour, electrical behaviour, and notch sensitivity. Unfilled PA12 has high elongation and low hardness but limited creep resistance and high thermal expansion; a 20 wt% carbon fibre compound reduces linear thermal expansion from roughly 90–120 µm/m·K for neat PA12 to 25–45 µm/m·K in the flow direction when measured according to ISO 11359-2:2021. Compared with a 30 wt% glass fibre PA12 reference, carbon fibre grades have lower density and higher modulus per unit mass, but the anisotropic electrical conductivity of carbon fibre can create galvanic corrosion concerns when direct contact with dissimilar metals is present in humid environments. Glass fibre is electrically insulating; carbon fibre grades may show surface resistivity below 106 Ω/sq under IEC 62631-3-2:2016, which is useful for electrostatic dissipation but restricts high-voltage isolation. Carbon fibre also reduces the coefficient of friction against steel and improves wear resistance, though the counterface may be polished by the carbon fibre. In applications requiring dimensional stability at 60–80 °C and 50% RH, PA12-CF generally exhibits lower moisture uptake and more stable mechanical retention than PA6-CF and PA66-CF because the polyamide 12 matrix absorbs less water.
Pre-drying conditions for carbon-fibre-filled PA12 are not optional prior to injection moulding or extrusion. The compound should be dried in a desiccant dryer at 80 °C for 4–8 h to a residual moisture level below 0.1%, measured by ISO 15512:2019 or a calibrated Karl Fischer apparatus. If hopper residence time during humid production exceeds 2 h, secondary drying or a dew-point-controlled hopper with a supply air dew point of −40 °C is required. Melt temperature should remain between 230 °C and 260 °C; prolonged residence above 270 °C initiates oxidative degradation that darkens the compound and reduces molecular weight. Mould temperature of 80–100 °C is used for thin-walled structural parts to promote fibre wet-out and reduce frozen-in orientation. Screw and barrel wear is a defined operational boundary: carbon fibre compounds require bimetallic barrel lining and a hardened screw flight, typically with a chromium or tungsten carbide coating, to prevent premature diameter loss. A general-purpose screw with an L/D ratio of 20:1 to 24:1 and a compression ratio of 2.0:1 to 2.5:1 is typical; high-shear mixing elements are avoided because they fracture fibre length and reduce modulus. Back pressure is kept at 0.3–0.7 MPa to avoid excessive fibre breakage. Injection speed follows medium-to-fast settings: too slow produces freeze-off and exposed fibre at the surface; too fast can cause jetting and weld-line weakness. Packing pressure between 50% and 80% of peak injection pressure is commonly used, with hold time set by gate freeze. Contamination with other polyamides such as PA66 should be avoided because the higher melting point of PA66 produces unmelted inclusions above PA12 processing temperatures.
At 30 wt% carbon fibre loading, tensile modulus approaches 15,000–20,000 MPa, but the compound becomes more viscous, more notch-sensitive, and more anisotropic than the 20 wt% grade. The melt flow rate measured at 275 °C with a 5 kg load according to ISO 1133-1:2022 is significantly lower than unfilled PA12; machine selection must ensure adequate plasticating capacity rather than relying on standard moulding parameters. Gate and runner sizing should account for higher melt viscosity; gate dimensions are often increased by 20–40% relative to unfilled PA12 to prevent premature freeze-off. Weld-line tensile strength in carbon fibre compounds is typically lower than the bulk tensile strength because fibre orientation across the weld line is discontinuous; published data for this specific configuration is limited, but design reviews commonly apply a weld-line knock-down factor of 0.5–0.7 for structural ribs and bosses unless validated by coupon testing using ISO 527-2/1A specimens. In thin sections below 1.5 mm, carbon fibre can produce surface roughness and resin-rich areas; mould filling studies with short shots are recommended. Warpage is not eliminated by carbon fibre; anisotropic shrinkage between flow and cross-flow directions can exceed 0.1% and must be compensated through gate placement and mould temperature uniformity.
For automotive underhood snap-fit brackets and pneumatic system housings, PA12-CF with 20 wt% fibre is specified over PA66-CF when low-temperature impact at −40 °C, road salt exposure, and mineral oil resistance are required. PA12 retains ductility below −40 °C better than PA66; carbon fibre reinforcement reduces elongation but the matrix remains less brittle than PA66-CF in U-shaped inserts and clip arms. Medical orthotic shells and prosthetic sockets use 10–20 wt% carbon fibre PA12 because the compound is lighter than glass-filled polyamide and can be post-formed after heating to 160–180 °C. In compressed-air fittings, PA12-CF provides lower moisture uptake than PA6-CF and better dimensional stability after conditioning at 23 °C/50% RH according to ISO 1110:2019. However, the material is not universally suitable: direct food-contact status requires grade-specific FDA 21 CFR 177.1500 confirmation, and carbon fibre filler is not automatically covered by food-contact notifications. For high-voltage electrical housings, the reduced surface resistivity of carbon fibre grades may violate creepage and clearance design rules under IEC 60664-1:2020, and glass-filled PA12 or unfilled PA12 is preferred.
Surface resistivity in carbon-fibre-filled PA12 depends on fibre volume fraction, fibre length retention, and the presence of conductive additives. A 20 wt% carbon fibre compound may exhibit surface resistivity in the 103–106 Ω/sq range when measured according to IEC 62631-3-2:2016, but the value is not guaranteed in dry-as-moulded parts after resin-rich surface layers form. Higher carbon fibre loadings reduce surface resistivity and improve electrostatic dissipation; lower loadings below 10 wt% may remain essentially insulating. The user should define whether the requirement is static decay, surface resistance, or volume resistance, because each test uses different electrode configurations and conditioning. For explosive atmosphere equipment, the material must be tested against the applicable IEC 60079-0:2017 requirements; the presence of conductive carbon fibre does not automatically qualify a component as antistatic or conductive. Galvanic coupling with aluminium or magnesium housings is a known risk when moisture is present, and insulation washers or coatings are applied to interrupt the conductive path. In rail interiors, fire-smoke-toxicity requirements such as EN 45545-2 are grade-specific and cannot be assumed from the base polymer type alone.
| Requirement | Designation | Typical assessment |
|---|---|---|
| REACH SVHC declaration | EC 1907/2006 | Required from compounder; carbon fibre sizing may contain specific substances |
| RoHS restricted substances | 2011/65/EU and (EU) 2015/863 | Lead, mercury, cadmium, hexavalent chromium, PBB, PBDE and phthalates below maximum concentration values |
| Food contact | FDA 21 CFR 177.1500 / EC 10/2011 | Grade-specific confirmation; carbon fibre filler not automatically covered |
| Flammability | UL 94 | HB or V-2 typical; V-0 requires flame-retardant modification |
| Surface resistivity | IEC 62631-3-2:2016 | Grade-dependent; validate on moulded parts, not raw pellets |
| Thermal measurements | ISO 75-2:2013, ISO 11357-3:2018 | HDT and melting peak used for processing and end-use limits |
Sliding contact applications impose counterface roughness limits and require break-in protocols to prevent transfer film disruption. Carbon-fibre-filled PA12 against hardened steel with surface roughness below 0.2 µm Ra can generate a stable transfer film that reduces wear rate; rougher counterfaces cause fibre pull-out and abrasive third-body wear. Filled compounds with carbon fibre exhibit lower wear than glass fibre compounds in dry sliding, but the wear rate is sensitive to contact pressure above 1.0 MPa and sliding velocity above 1 m/s. Published data for this specific configuration is limited for continuous sliding above 1 m/s; end-use tests using ASTM G133-05 or a block-on-ring configuration are required. Dimensional tolerances should account for moisture swell and thermal expansion; the coefficient of linear thermal expansion is isotropic only in unfilled material and becomes flow-direction-dependent in carbon-fibre compounds. Machine shops often report that carbon-fibre PA12 produces conductive dust that must be extracted to prevent electrical shorting in assembly cells.
